Rotor construction



United States Patent ROTOR CONSTRUCTION Walter A. Ledwith, Glastonbury, Conn., assignor to United Aircraft Corporation, East Hartford, Conn., a corporation of Delaware Application November 13, 1950, Serial No. 195,256

6 Claims. (Cl. 253-39) The present inyention relates to rotor constructions particularly for use in axial flow compressors or turbines.

For facilitating manufacture and replacement of parts, it is common to build rotors out of a number of axially spaced discs with a row of blades located on the periphery of each disc and with the discs clamped together by one or more axially extending bolts, one example of this type of construction being shown in the Soderberg Patent No. 2,461,242. One of the problems has been the accurate alignment of the several discs. A feature of this invention is a simplified arrangement for providing accurate axial alignment of the several discs making up the rotor.

Another feature of the invention is the combination with the aligning means of sealing flanges adapted to cooperate with the stationary diaphragms of the device in which the rotor is located.

Other objects and advantages will be apparent from the specification and claims, and from the accompanying drawings which illustrate an embodiment of the invention.

Fig. 1 is a fragmentary sectional view through a compressor incorporating the invention.

Fig. 2 is an enlarged fragmentary view showing a detail.

The invention is shown in an axial flow compressor which includes a casing 2 having a number of inwardly extending rows 4 of vanes which are spaced apart for the reception of rows 6 of blades therebetween. Each row of blades 6 is carried by one of a plurality of discs 8, 8a and 8b,and the assembly of discs is held together axially by a through bolt 10. In the arrangement shown, one of the discs 8 is in the form of an end bell having a laterally projecting sleeve 12 for engagement with the bearings 14 which support the rotor.

Each of the discs 8 (with the exception of the endmost disc) has laterally projecting flanges 16 with all of these flanges preferably of the same diameter. The outer end of each of the flanges has an integral ring 18, the inner surface 26 of which is axially extending and concentric to the axis of the disc. Ring 18 also has a radially extending surface 50. Complete flange 16 including ring 18 is L-shaped in cross-section. Between adjacent discs and engaging with the rings 18 on the ends of the flanges 16 is a piloting ring 20 which as best shown in Fig. 2 has a base section 22 having axially extending surfaces 24 cooperating with the axially extending and innermost surfaces 26 of the rings 18 on the flanges to support the discs 8 in concentric relation. The ring 20 has a central portion 28 with radially extending side surfaces 52. Central portion 28 extends outwardly from the base 22 between adjacent rings 18 and carries a number of axially extending pins 30 positioned in holes 32 in the ring and extending into recesses 34 in the disc rings 18 thereby, when the rotor is in operation, transmitting torque between adjacent discs.

The outer periphery of the piloting ring 20 may be provided with one or more sealing flanges 36 which project outwardly and are preferably turned down at their outer edge for location in closely spaced relation to the inner shroud ring 38 on the ends of the stationary vanes 4. By this arrangement the piloting ring 20 functions not only for the axial alignment of adjacent discs, but also provides the sealing flanges which prevent leakage of the fluid around the shroud 38. It may be noted that the recesses 34 which receive the pins 30 extend the full axial dimension of ring 18 and are reduced in diameter,

2,702,687 Patented Feb. 22, 1955 2 as shown at 40 (Fig. 2) beyond the ends of the pins 30, thereby preventing the pins from working loose during the operation of the device.

It is to be understood that the invention is not limited to the specific embodiment herein illustrated and described, but may be used in other ways without departulre from its spirit as defined by the following claims.

I c aim:

1. A rotor including a number of discs, annular flanges on opposite sides of each disc and concentric thereto, pilot rings between adjacent annular flanges of the discs, said pilot rings having opposite side surfaces extending radially, and said annular flanges having end surfaces which extend radially and engage the radially extending side surfaces of the pilot rings such that the rings support the discs in axial relation to one another, and a single row of axially extending pins extending through each pilot ring with the ends projecting beyond the side surfaces of the ring, said annular flanges having axially extending openings receiving the ends of said pins, the latter thereby transmitting torque between adjacent discs.

2. A rotor including a number of discs, annular flanges on opposite sides of each disc and concentric thereto, said annular flanges having axially extending inner surfaces, one piece pilot rings between adjacent annular flanges of the discs, said pilot rings engaging radially with said annular flanges for supporting the discs in axial relation, and further engaging the inner surfaces of said annular flanges for the purpose of piloting said discs during assembly and operation, and a single row of axial pins positioned in openings in each of the pilot rings and extending beyond the rings on both sides, said annular flanges having axially extending openings therein, and each said pin engaging with said openings provided in the adjacent annular flanges for transmitting torque between the discs.

3. A rotor including a number of discs, annular flanges on opposite sides of each disc and concentric thereto, pilot rings between adjacent annular flanges of the discs, said annular flanges and said pilot rings having both radially and axially extending surfaces, said axially extending surfaces of said piloting rings engaging said axially extending surfaces of said annular flanges to support the discs in concentric relation, and a single row of axial pins positioned in openings in each of said pilot rings and extending beyond the rings on both sides, said flanges having axially extending openings therein, and said pins engaging in said openings provided in the adjacent annular flanges for transmitting torque between the discs, said ring having peripherally extending integral sealing flanges.

4. A casing having a plurality of rows of vanes extending inwardly therefrom with a ring carried by the inner ends of each row of vanes, in combination with a rotor within said casing, said rotor including a number of discs having annular flanges on opposite sides thereof and concentric thereto, said annular flanges having both axially extending and radially extending surfaces, pilot rings between adjacent annular flanges having axially extending surfaces which mate with the axially extending surfaces of said flanges to support said discs in concentric relation and also having radially extending surfaces which mate with the radially extending surfaces of said flanges to axially space said discs, said pilot rings having sealing flanges on the peripheries thereof to cooperate with the rings carried by the inner ends of the rows of vanes, and a single row of axial pins extending through each pilot ring with the ends projecting beyond the radially extending surfaces of the pilot rings, said flanges having axially extending openings receiving the ends of the said pins, the latter thereby transmitting torque between adjacent discs.

5. A rotor including a plurality of discs, annular flanges integral with and located on opposite sides of the discs and concentric thereto, pilot rings between adjacent annular flanges having both radially extending and axially extending surfaces, each of said annular flanges being substantially L-shaped in cross section and having both a radially extending end surface and an axially extending surface and having a plurality of multi-diameter concentric recesses in their radially extending end surfaces and extending axially the full axial dimension of ,said flanges, the axial surfaces of' said rings engaging the axial surfaces of said annular flanges to'support said discs in concentric relation and said radial surfaces of said annular flanges engaging the radial surfaces of said rings to position said discs in spaced axial relation, 3. single 7 row of axial pins extending through and being carried by and projecting on both sides of said rings, each of said pins engaging said annular flanges of adjacent discs by extending into and being held in tight engagement 'by said multi-diameter concentric recesses in the radially extending end surfaces of said annular flanges to transmit torque between the discs, said pilot rings having a plurality of radially extending sealing flanges attached to 'the periphery of said rings, and means passing through said discs for holding said discs together axially.

6. A rotor including a number of discs, annular axially extending surfaces on opposite sides of each of said rings, axially extending surfaces on each of said an nular flanges, each of said axially extending surfaces on said rings engaging said axially extending surfaces on said adjacent annular flange whereby said rings pilot the adjacent discs and hold them in concentric relation to each other, a single row of axially extending pins extending through each pilot ring with theends projecting beyond the side surfaces of the ring, said annular flanges having axially extending openings receiving the ends of said pins, the latter thereby'transrnitting torque between adjacent discs.

References Cited in the file of this patent UNITED STATES PATENTS Great Britain Apr. 11, 1949 

